Storyline
Tae Gong Shil gets the request from ghosts to find a way to warm the hearts of everyone in the world. With the help of Kang Woo, who introduces her to Kim Tan, Tae Gong Shil is able to get the help of Cha Eun Sang. Cha Eun Sang asks the question "When do people's hearts become warm?" on her social network account: various characters and idols answer in different ways that music warms their hearts.